We caught up with Primary Weapon Systems at SHOT Show 2026 in Las Vegas, and the company has some intriguing designs headed out to the market.

PWS is best known for its long-stroke piston systems, which blend features found in the AK operating system with the AR-15 platform. The design helps eliminate a lot of the heat and fouling that works its way into the action on things like direct-impingement systems. 

Fans of .308 Win will appreciate the return of that caliber in the MK2 AR-10s featuring a longer piston rod. The MK2s include an adjustable gas regulator for fine-tuning the guns for suppressed and unsuppressed shooting needs.

A particularly unique feature of the MK2 system is PWS’s patent-pending Bore Evacuation Chamber. It’s akin to the bulge seen on the famous M1 Abrams tank barrels, and that helps pull the pressurized gas out the front of the barrel instead of flowing backward into the action.

We’ve got more details on the MK2 and other additions to the PWS family, including the company’s line of titanium suppressors with customizable sizes that use removable baffles. 

Check it all out in the video above.